(1) Soil "baking" induced sharp changes of the regimes of water,air and warmth of the rice-field soils,and hence also induced sharp changes in amount and composition of microorganisms.Experimental data shew that there were significant increases in total count,bacteria,actinomycetes and fungi.The ratio of aerobic to anaerobic microorganisms also significantly changed,aerobes increased in number while anaerobes decreased.Obviously,these changes were beneficial to the mineralization of organic N and P,raising up the regimes of N and P nutrients.